... 2032 button Material:silica gel+PP 8.5cm Length+3cm Head Diameter silicone led bicycle light 8.5cm Length+3cm Head Diameter Powered ... by CR2032 (included) Material:silica gel+PP2 bright led Light weight, easy ... .It can be mounted on bicycle handle, seatpost, helmet, wheel, bag and so on Available colours,White, Black, Red, Green, Blue, ...